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Home > Cats > Can Cats Drink Soy Milk? Vet-Reviewed Facts & FAQ

Can Cats Drink Soy Milk? Vet-Reviewed Facts & FAQ

a glass of soymilk and bowl of soybeans

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Dr. Lorna Whittemore Photo

Reviewed & Fact-Checked By

Dr. Lorna Whittemore

Veterinarian, MRCVS

The information is current and up-to-date in accordance with the latest veterinarian research.

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Soy is a popular substitute for dairy for people worldwide. As more people are consuming soy milk, there’s been a lingering question if our furry companions, such as cats, can also drink soy milk.

Although not toxic to cats, soy carries almost no nutritional benefits for felines, so your cat is better off without drinking soy. Of course, that doesn’t mean something bad will happen to your cat if it does drink soy milk; unless they have a soy allergy. Providing it however is not necessary or a useful addition to their diet.

In this article, we’ll talk more about cats and soy milk, along with the possible problems that may arise if your feline drinks soy milk.


What Is Soy?

Soy is a plant-based protein native to Asia; it’s common in various store-bought products, such as:

Soy milk: Made from grounded and filtered soybeans
Tofu: Soy beverage that’s curdled and pressed
Edamame: Fresh boiled green soybeans, mainly sold frozen
Soy sauce:
A liquid sauce mainly used in Asian cuisine made of fermented soybeans
Miso: Fermented soybean paste

Traces of soy could also be found in products such as chocolates, ice creams, and similar foods. It’s a common ingredient in the diet of vegetarians and vegans.

Image Credit: feeling lucky, Shutterstock

Can Cats Drink Soy Milk? Is Drinking Soy Milk Safe for Cats?

All cats are obligate carnivores, meaning they require meat and meat-based protein in their diet to survive. As their dietary needs can only be supplied by consuming animal meat, cats don’t need many plant-based foods and non-meat items.

Plant food sources and non-meat items like soy milk can’t provide enough nutrients and proteins your cat needs. However, if you provide soy milk or other non-meat items, it’s likely your cat will try them out of curiosity.

That said, if your cat drinks soy milk out of curiosity, there’s no need to panic. If this doesn’t happen frequently, your feline probably won’t experience any issues.

Still, soy milk is not the safest food for your cat to consume; cats who frequently drink soy milk might experience health problems.

Domestic cat sitting on the carpet and drinking milk from bowl in the room at home
Image Credit: AnnaStills, Shutterstock

Problems Your Cat May Experience After Drinking Soy Milk

As the name says, soy milk is mainly made out of soy, although it may contain traces of other ingredients. Soy could have a negative effect on your cat and its health due to several reasons.

According to one small study about the effect of dietary soy on serum thyroid hormone concentrations in healthy adult cats, soy protein increased the thyroid hormones above normal and could therefore contribute to hyperthyroidism.

Several young, healthy adult cats participated in this research, which included the researchers providing cats with either a soy-free or a soy-inclusive diet for three months.

The results show that the cats who consumed soy products every day had higher concentrations of T3 and T4, which are connected with hyperthyroidism in cats.

Another issue that cats who drink soy may experience is food allergies; cats can’t process soy protein the same way they process meat protein, potentially resulting in allergic reactions. Some symptoms of soy allergies in cats may include:

  • Itching
  • Irritated/red skin
  • Hair loss
  • Vomiting
  • Diarrhea
  • GI issues
  • Excessive scratching

What Will Happen if My Cat Drinks Soy Milk?

If your cat accidentally drank soy milk as a sign of curiosity and is showcasing absolutely no problems, there’s nothing you should worry about. However, some cats may develop an allergic reaction to soy milk, which is why you should monitor your feline and contact your vet if you notice any allergy signs.

As soy and soy milk could potentially be harmful to cats and affect your feline’s thyroid gland, it’s best to avoid this product in your cat’s diet.


Final Thoughts

Cats can drink soy milk, but it’s still not something they should do. Consuming soy milk, especially frequently and in large amounts, could lead to food allergies and hyperthyroidism in your cat, so it’s better to be safe than sorry and avoid soy milk unless you’re the one drinking it.

Featured Image Credit: Makistock, Shutterstock

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